I would suggest to add two more intermediate variables:

var allTriggersAvailable = meterFlag && workFlag && timeFalg;
var anyTriggerAvailable = meterFlag || workFlag || timeFalg;

if (allTriggersAvailable || (!IsAllTriggersRequired && anyTriggerAvailable))
{
    result.Add(new TodayTaskTest { Code = item1.Code, Id = item1.Id, Title = item1.Title });
}

I would suggest to add two more intermediate variables:

var allTriggersAvailable = meterFlag && workFlag && timeFlag;
var anyTriggerAvailable = meterFlag || workFlag || timeFlag;

if (allTriggersAvailable || (!IsAllTriggersRequired && anyTriggerAvailable))
{
    result.Add(new TodayTaskTest { Code = item1.Code, Id = item1.Id, Title = item1.Title });
}